Pitching single-focus confocal data analysis one photon at a time with Bayesian nonparametrics.
Pitching single-focus confocal data analysis one photon at a time with Bayesian nonparametrics.
复制标题
使用贝叶斯非参数分析一次一个光子进行单焦点共焦数据分析。
DOI：
10.1103/physrevx.10.011021
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发表时间：
2020
期刊：
影响因子：
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通讯作者：
Pressé,Steve
中科院分区：
文献类型：
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作者：
Tavakoli,Meysam;Jazani,Sina;Sgouralis,Ioannis;Shafraz,OmerM;Sivasankar,Sanjeevi;Donaphon,Bryan;Levitus,Marcia;Pressé,Steve
荧光时间轨迹用于报告分子的动力学性质。这些轨迹中的基本信息单位是单个光子的到达时间，这些光子携带着从发射它们的分子到检测器的瞬时信息，其时间尺度快至微秒。因此，从理论上讲，可以从仅包含足够数量的光子到达的轨迹中监测这样的时间尺度上的分子动力学。然而，在实践中，痕迹是随机的，为了通过传统的手段，如荧光相关光谱（FCS）和相关技术推导出动态信息，他们收集和时间自相关超过几分钟。到目前为止，它一直是不可能的分析分子的动力学性质的时间尺度上接近数据采集，而不收集长的痕迹下的观测过程的平稳性或相关函数的分析推导所需的假设的强假设。为了避免这些假设，我们需要估计发射光子的分子的瞬时数量及其在共焦体积内的位置。由于在一个典型的实验中分子的数量是未知的，这个问题要求我们放弃传统的分析范式。在这里，我们利用贝叶斯nonparametrics，使我们能够获得，在一个原则性的方式，估计相同数量的FCS，但从直接分析的痕迹光子到达的大小，或总持续时间显着小于FCS所需的。
Fluorescence time traces are used to report on dynamical properties of molecules. The basic unit of information in these traces is the arrival time of individual photons, which carry instantaneous information from the molecule, from which they are emitted, to the detector on timescales as fast as microseconds. Thus, it is theoretically possible to monitor molecular dynamics at such timescales from traces containing only a sufficient number of photon arrivals. In practice, however, traces are stochastic and in order to deduce dynamical information through traditional means—such as fluorescence correlation spectroscopy (FCS) and related techniques—they are collected and temporally autocorrelated over several minutes. So far, it has been impossible to analyze dynamical properties of molecules on timescales approaching data acquisition without collecting long traces under the strong assumption of stationarity of the process under observation or assumptions required for the analytic derivation of a correlation function. To avoid these assumptions, we would otherwise need to estimate the instantaneous number of molecules emitting photons and their positions within the confocal volume. As the number of molecules in a typical experiment is unknown, this problem demands that we abandon the conventional analysis paradigm. Here, we exploit Bayesian nonparametrics that allow us to obtain, in a principled fashion, estimates of the same quantities as FCS but from the direct analysis of traces of photon arrivals that are significantly smaller in size, or total duration, than those required by FCS.